In the dynamic industry of circuit design, the goal is always to develop components that are smaller and more efficient. The basic module of all digital circuits is the gate. Unlike analog circuits, digital circuits can have a few discrete input states. A gate is a simple digital circuit that produces a specific, predictable output condition for each possible input condition. When a gate is combined with other gates, they are able to perform complex logical and arithmetic operations. Gates are the physical realization of simple Boolean expressions. A gate's operation may be described in mathematical terms and Boolean algebra may be used for analyzing a circuit having gates.
A common gate in digital logic design is the inclusive OR gate which performs the Boolean operation of disjunction. A Boolean variable has one of two values, such as 1 or 0 that are often referred to as TRUE or FALSE. In an electronic system there is either a voltage present to represent a value of 1 or no voltage present to represent a value of 0. Most computer languages, C++, FORTRAN, and BASIC, represent TRUE as non-zero and FALSE as 0. For input variables of 0 or 1, the inclusive OR gate outputs a value of 1 if one or more of its inputs values are 1. The inclusive OR gate output value of 0 only if all input values are 0. The term “OR gate” without a qualifier is generally taken to be an inclusive OR gate.
The OR gate may be implemented with relatively few components. For example, an OR gate may include two diodes in parallel or two transistors in parallel. In the transistor example, a gate voltage for one or both of the transistors provides a 1 value output. As can be expected, a vast number of OR gates are required in complex circuits. Even slight reductions in the size of an OR gate would result in significant improvements to the overall architecture
It would be an advancement in the art to provide an OR gate circuit that is smaller, more efficient, and has superior gate voltage control. Such a device is disclosed and claimed herein.